<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>三角形</title>

    <style>
        .box {
            width: 0px;
            height: 0px;
            border-top: 50px solid transparent;
            border-bottom: 0px solid yellow;
            border-left: 0px solid violet;
            border-right: 25px solid white;
            position: relative;
            right: 50px;
            float: left;
        }
        
        .box2 {
            width: 100px;
            height: 50px;
            float: left;
            position: relative;
            right: 50px;
            background-color: white;
            line-height: 50px;
            text-align: center;
            color: darkgray;
            font-weight: 800;
        }
        
        .box3 {
            width: 150px;
            height: 50px;
            line-height: 50px;
            text-align: left;
            padding-left: 50px;
            float: left;
            color: white;
            font-weight: 800;
            background-color: tomato;
        }
        
        .nav {
            position: absolute;
            border: 1px solid tomato;
        }
    </style>


</head>

<body>

    <div class="nav">
        <div class="box3">
            <span> $1405</span>
        </div>
        <div class="box"></div>
        <div class="box2">
            <span><del>$1243.62</del></span>
        </div>
    </div>


</body>

</html>